Most people choose to ride the C&O Canal on a bicycle. I chose to take my time and walk the whole 184.5 miles from Washington DC to Cumberland, MD.
The C&O Canal is a great introduction to long distance hiking for people that have very little experience. It is relatively flat, easy to navigate and it has free campgrounds for hikers and cyclists along its entire route. That makes it a very cheap vacation to see if you like this long distance hiking thing. (I spent very little $$ the entire hike, and that included transportation to the trail, with the exception of a hostel stay/splurge in the middle)
The campsites also offer pumps with iodine treated water along the route. Some of them may be dry but for the most part they were a great resource to have while hiking.
It only took me eight days to hike the entire trail end to end, I’d planned on at least ten but I have a hard time slowing down even with blisters.
The highlight of the trail is definitely the Paw Paw Tunnel but there is a lot of US history along its route as this was the main dividing line during the Civil War.
To plan a hike you’ll need little more than the freely available National Parks Service maps of the trail. I liked the fact that it was easy enough to get out of a major city like Washington DC and be able to walk to a free and relatively remote place to legally camp.
That and technically you could probably spend a month or more walking up and down the C&O Canal living and camping for free while spending most of the summer swimming and getting a tan.